A set of network devices may perform network traffic routing for a network. For example, a particular network device housed in a chassis may include a set of switch interface boards (SIBs) that provide a switching functionality for the particular network device. The set of switch interface boards may be configured in the particular network device to provide a switching fabric for the particular network device. A switching fabric may include a network topology of network nodes interconnected via the set of switch interface boards. The set of switch interface boards may be installed to operate in a particular configuration, such as a first operation mode for intra-chassis routing or a second operation mode for inter-chassis routing. To perform inter-chassis routing, the switch interface board may transmit network traffic to a cross-connect chassis, which is connected to multiple other chassis, for further routing.